The structure of LaSr2CuTiO6.5, a novel (ABO3)nAO n = 2 Ruddlesden-Popper phase, has been solved by powder X-ray diffraction and electron microscopy. The diffraction patterns are consistent with I4/mmm symmetry, with tetragonal lattice parameters a = 3.8816(1) Å and c = 20.296(2) Å. The structure of LaSr2CuTiO6.5 is similar to Sr3Ti2O7, with copper and titanium disordered over the single B-cation site, and lanthanum and strontium almost perfectly disordered over the two A-cation sites. The oxygen content, determined by thermogravimetric reduction to be 6.5 (±0.1), is consistent with divalent copper with the oxygen vacancies distributed within the perovskite layers. The absence of local order and strategies for inducing a layered arrangement of the B-cations are discussed.
|Original language||English (US)|
|Number of pages||7|
|Journal||Chemistry of Materials|
|State||Published - Dec 1 1996|
ASJC Scopus subject areas
- Chemical Engineering(all)
- Materials Chemistry